impatient to engage; but the Barbarians, after a slight resistance, fled in disorder; unable to resist, or desirous to weary, the strength of the heavy legions, who, fainting with heat and thirst, pursued them across the plain, and cut in pieces a line of cavalry, clothed in complete armor, which had been posted before the gates of the camp to protect their retreat. Constantius, who was hurried along in the pursuit, attempted, without effect, to restrain the ardor of his troops, by representing to them the dangers of the approaching night, and the certainty of completing their success with the return of day. As they depended much more on their own valor than on the experience or the abilities of their chief, they silenced by their clamors his timid remonstrances; and rushing with fury to the charge, filled up the ditch, broke down the rampart, and dispersed themselves through the tents to recruit their exhausted strength, and to enjoy the rich harvest of their labors. But the prudent Sapor had watched the moment of victory. His army, of which the greater part, securely posted on the heights, had been spectators of the action, advanced in silence, and under the shadow of the night; and his Persian archers, guided by the illumination of the camp, poured a shower of arrows on a disarmed and licentious crowd. The sincerity of history declares, that the Romans were vanquished with a dreadful slaughter, and that the flying remnant of the legions was exposed to the most intolerable hardships. Even the tenderness of panegyric, confessing that the glory of the emperor was sullied by the disobedience of his soldiers, chooses to draw a veil over the circumstances of this melancholy retreat. Yet one of those venal orators, so jealous of the fame of Constantius, relates, with amazing coolness, an act of such incredible cruelty, as, in the judgment of posterity, must imprint a far deeper stain on the honor of the Imperial name. The son of Sapor, the heir of his crown, had been made a captive in the Persian camp. The unhappy youth, who might have excited the compassion of the most savage enemy, was scourged, tortured, and publicly executed by the inhuman Romans.

Whatever advantages might attend the arms of Sapor in the field, though nine repeated victories diffused among the nations the fame of his valor and conduct, he could not hope to succeed in the execution of his designs, while the fortified towns of Mesopotamia, and, above all, the strong and ancient city of Nisibis, remained in the possession of the Romans. In the space of twelve years, Nisibis, which, since the time of Lucullus, had been deservedly esteemed the bulwark of the East, sustained three memorable sieges against the power of Sapor; and the disappointed monarch, after urging his attacks above sixty, eighty, and a hundred days, was thrice repulsed with loss and ignominy. This large and populous city was situate about two days' journey from the Tigris, in the midst of a pleasant and fertile plain at the foot of Mount Masius. A treble enclosure of brick walls was defended by a deep ditch; and the intrepid resistance of Count Lucilianus, and his garrison, was seconded by the desperate courage of the people. The citizens of Nisibis were animated by the exhortations of their bishop, inured to arms by the presence of danger, and convinced of the intentions of Sapor to plant a Persian colony in their room, and to lead them away into distant and barbarous captivity. The event of the two former sieges elated their confidence, and exasperated the haughty spirit of the Great King, who advanced a third time towards Nisibis, at the head of the united forces of Persia and India. The ordinary machines, invented to batter or undermine the walls, were rendered ineffectual by the superior skill of the Romans; and many days had vainly elapsed, when Sapor embraced a resolution worthy of an eastern monarch, who believed that the elements themselves were subject to his power. At the stated season of the melting of the snows in Armenia, the River Mygdonius, which divides the plain and the city of Nisibis, forms, like the Nile, an inundation over the adjacent country. By the labor of the Persians, the course of the river was stopped below the town, and the waters were confined on every side by solid mounds of earth. On this artificial lake, a fleet of armed vessels filled with soldiers, and with engines which discharged stones of five hundred pounds weight, advanced in order of battle, and engaged, almost upon a level, the troops which defended the ramparts. *The irresistible force of the waters was alternately fatal to the contending parties, till at length a portion of the walls, unable to sustain the accumulated pressure, gave way at once, and exposed an ample breach of one hundred and fifty feet. The Persians were instantly driven to the assault, and the fate of Nisibis depended on the event of the day. The heavy-armed cavalry, who led the van of a deep column, were embarrassed in the mud, and great numbers were drowned in the unseen holes which had been filled by the rushing waters. The elephants, made furious by their wounds, increased the disorder, and trampled down thousands of the Persian archers. The Great King, who, from an exalted throne, beheld the misfortunes of his arms, sounded, with reluctant indignation, the signal of the retreat, and suspended for some hours the prosecution